An electrical connector such as the electrical connector 50 shown in FIG. 1 may include a housing 55 and one or more modular lead frame assemblies 100. The lead frame assembly 100 is also shown in FIG. 2. Each lead frame assembly 100 may be an insert molded lead frame assembly. The lead frame assembly 100 may include an electrically insulating lead frame housing 108 through which contacts 104 extend. The lead frame housing 108 may be made of a dielectric material such as plastic. The lead frame assembly 100 may be constructed from as little material as possible, and the contacts 104 may be insulated from one another using air as a second dielectric. The use of air may provide for a decrease in cross-talk and for a low-weight connector, as compared to a connector that uses a heavier dielectric material throughout. However, such a connector may not be readily installed using standard flat rock tooling.